Systems and methods for distributed API gateways

ABSTRACT

Disclosed embodiments are directed at systems, methods, and architecture for providing microservices and a plurality of APIs to requesting clients. The architecture is a distributed cluster of gateway nodes that jointly provide microservices and the plurality of APIs. Providing the APIs includes providing a plurality of plugins that implement the APIs. As a result of a distributed architecture, the task of API management can be distributed across a cluster of gateway nodes. The gateway nodes effectively become the entry point for every API-related request. Some embodiments of the disclosed technology describe an auto-documentation plugin that can automatically generate documentation for an API by monitoring, parsing, and sniffing requests/responses to/from the API.

BACKGROUND

Application programming interfaces (APIs) are specifications intended to be used as interfaces by software components to communicate with each other. For example, APIs can include specifications for routines, data structures, object classes, and variables. Thus, an API defines what information is available and how to send or receive that information.

Setting up multiple APIs can be a challenge. This is because deploying an API requires tuning the configurations or settings of each API individually. Because API functionalities are individually tied to each API and servers hosting multiple APIs have to be individually set up for hosting the APIs, this makes it very difficult to build new APIs or even scale and maintain existing APIs. This becomes even more challenging when there are tens of thousands of APIs and millions of clients requesting API-related services per day. Consequently, this results in reduced system productivity.

SUMMARY

In some aspects, the disclosed technology describes how to install middleware in a distributed micro services API gateway nodes that is part of a cluster.

In some other aspects, the disclosed technology describes how to generate auto-documentation for an API by monitoring, parsing, and sniffing requests/responses to/from the API.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a prior art approach with multiple APIs having functionalities common to one another;

FIG. 1B illustrates a distributed API gateway architecture, according to an embodiment of the disclosed technology;

FIG. 2 illustrates a block diagram of an example environment suitable for functionalities provided by a gateway node, according to an embodiment of the disclosed technology;

FIG. 3A illustrates a block diagram of an example environment with a cluster of gateway nodes in operation, according to an embodiment of the disclosed technology;

FIG. 3B illustrates a schematic of a data store shared by multiple gateway nodes, according to an embodiment of the disclosed technology;

FIG. 4A and FIG. 4B illustrate example ports and connections of a gateway node, according to an embodiment of the disclosed technology;

FIG. 5 illustrates a flow diagram showing steps involved in installation of a plugin at a gateway node, according to an embodiment of the disclosed technology;

FIG. 6 illustrates a sequence diagram showing components and associated steps involved in loading configurations and code at runtime, according to an embodiment of the disclosed technology;

FIG. 7 illustrates a sequence diagram of a use-case showing components and associated steps involved in generating auto-documentation, according to an embodiment of the disclosed technology;

FIG. 8 illustrates a sequence diagram of another use-case showing components and associated steps involved in generating auto-documentation, according to an embodiment of the disclosed technology;

FIG. 9 illustrates a flow diagram showing steps involved in generating auto-documentation, according to an embodiment of the disclosed technology;

FIG. 10 depicts a diagrammatic representation of a machine in the example form of a computer system within which a set of instructions, for causing the machine to perform any one or more of the methodologies discussed herein, may be executed.

DETAILED DESCRIPTION

The following description and drawings are illustrative and are not to be construed as limiting. Numerous specific details are described to provide a thorough understanding of the disclosure. However, in certain instances, well-known or conventional details are not described in order to avoid obscuring the description. References to an embodiment in the present disclosure can be, but not necessarily are, references to the same embodiment; and, such references mean at least one of the embodiments.

Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

The terms used in this specification generally have their ordinary meanings in the art, within the context of the disclosure, and in the specific context where each term is used. Certain terms that are used to describe the disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the disclosure. For convenience, certain terms may be highlighted, for example using italics and/or quotation marks. The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term is the same, in the same context, whether or not it is highlighted. It will be appreciated that same thing can be said in more than one way.

Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein, nor is any special significance to be placed upon whether or not a term is elaborated or discussed herein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and is not intended to further limit the scope and meaning of the disclosure or of any exemplified term. Likewise, the disclosure is not limited to various embodiments given in this specification.

Without intent to further limit the scope of the disclosure, examples of instruments, apparatus, methods and their related results according to the embodiments of the present disclosure are given below. Note that titles or subtitles may be used in the examples for convenience of a reader, which in no way should limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including definitions will control.

Embodiments of the present disclosure are directed at systems, methods, and architecture for providing microservices and a plurality of APIs to requesting clients. The architecture is a distributed cluster of gateway nodes that jointly provide microservices and the plurality of APIs. Providing the APIs includes providing a plurality of plugins that implement the APIs. As a result of a distributed architecture, the task of API management can be distributed across a cluster of gateway nodes. Every request being made to an API hits a gateway node first, and then the request is proxied to the target API. The gateway nodes effectively become the entry point for every API-related request. The disclosed embodiments are well-suited for use in mission critical deployments at small and large organizations. Aspects of the disclosed technology do not impose any limitation on the type of APIs. For example, these APIs can be proprietary APIs, publicly available APIs, or invite-only APIs.

FIG. 1A illustrates a prior art approach with multiple APIs having functionalities common to one another. As shown in FIG. 1A, a client 102 is associated with APIs 104A, 104B, 104C, 104D, and 104E. Each API has a standard set of features or functionalities associated with it. For example, the standard set of functionalities associated with API 104A are “authentication” and “transformations.” The standard set of functionalities associated with API 104B are “authentication,” “rate-limiting,” “logging,” “caching,” and “transformations.” Thus, “authentication” and “transformations” are functionalities that are common to APIs 104A and 104B. Similarly, several other APIs in FIG. 1A share common functionalities. However, it is noted that having each API handle its own functionalities individually causes duplication of efforts and code associated with these functionalities, which is inefficient. This problem becomes significantly more challenging when there are tens of thousands of APIs and millions of clients requesting API-related services per day.

FIG. 1B illustrates a distributed API gateway architecture according to an embodiment of the disclosed technology. To address the challenge described in connection with FIG. 1A, the disclosed technology provides a distributed API gateway architecture as shown in FIG. 1B. Specifically, disclosed embodiments implement common API functionalities by bundling the common API functionalities into a gateway node 106 (also referred to herein as an API Gateway). Gateway node 106 implements common functionalities as a core set of functionalities that runs in front of APIs 108A, 108B, 108C, 108D, and 108E. The core set of functionalities include rate limiting, caching, authentication, logging, transformations, and security. It will be understood that the above-mentioned core set of functionalities are for examples and illustrations. There can be other functionalities included in the core set of functionalities besides those discussed in FIG. 1B. In some applications, gateway node 106 can help launch large-scale deployments in a very short time at reduced complexity and is therefore an inexpensive replacement for expensive proprietary API management systems. The disclosed technology includes a distributed architecture of gateway nodes with each gateway node bundled with a set of functionalities that can be extended depending on the use-case or applications.

FIG. 2 illustrates a block diagram of an example environment suitable for functionalities provided by a gateway node according to an embodiment of the disclosed technology. In some embodiments, a core set of functionalities are provided in the form of “plugins” or “add-ons” installed at a gateway node. (Generally, a plugin is a component that allows modification of what a system can do usually without forcing a redesign/compile of the system. When an application supports plug-ins, it enables customization. The common examples are the plug-ins used in web browsers to add new features such as search-engines, virus scanners, or the ability to utilize a new file type such as a new video format.)

As an example, a set of plugins 204 shown in FIG. 2 are provided by gateway node 206 positioned between a client 202 and one or more HTTP APIs. Electronic devices operated by client 202 can include, but are not limited to, a server desktop, a desktop computer, a computer cluster, a mobile computing device such as a notebook, a laptop computer, a handheld computer, a mobile phone, a smart phone, a PDA, a BlackBerry™ device, a Treo™, and/or an iPhone or Droid device, etc. Gateway node 206 and client 202 are configured to communicate with each other via network 207. Gateway node 206 and one or more APIs 208 are configured to communicate with each other via network 209. In some embodiments, the one or more APIs reside in one or more API servers, API data stores, or one or more API hubs. Various combinations of configurations are possible.

Networks 207 and 209 can be any collection of distinct networks operating wholly or partially in conjunction to provide connectivity to/from client 202 and one or more APIs 208. In one embodiment, network communications can be achieved by, an open network, such as the Internet, or a private network, such as an intranet and/or the extranet. Networks 207 and 209 can be a telephonic network, an open network, such as the Internet, or a private network, such as an intranet and/or the extranet. For example, the Internet can provide file transfer, remote login, email, news, RSS, and other services through any known or convenient protocol, such as, but not limited to the TCP/IP protocol, Open System Interconnections (OSI), FTP, UPnP, iSCSI, NSF, ISDN, PDH, RS-232, SDH, SONET, etc.

Client 202 and one or more APIs 208 can be coupled to the network 150 (e.g., Internet) via a dial-up connection, a digital subscriber loop (DSL, ADSL), cable modem, wireless connections, and/or other types of connection. Thus, the client devices 102A-N, 112A-N, and 122A-N can communicate with remote servers (e.g., API servers 130A-N, hub servers, mail servers, instant messaging servers, etc.) that provide access to user interfaces of the World Wide Web via a web browser, for example.

The set of plugins 204 include authentication, logging, rate-limiting, and custom plugins, of which authentication, logging, traffic control, rate-limiting can be considered as the core set of functionalities. An authentication functionality can allow an authentication plugin to check for valid login credentials such as usernames and passwords. A logging functionality of a logging plugin logs data associated with requests and responses. A traffic control functionality of a traffic control plugin manages, throttles, and restricts inbound and outbound API traffic. A rate limiting functionality can allow managing, throttling, and restricting inbound and outbound API traffic. For example, a rate limiting plugin can determine how many HTTP requests a developer can make in a given period of seconds, minutes, hours, days, months or years.

A plugin can be regarded as a piece of stand-alone code. After a plugin is installed at a gateway node, it is available to be used. For example, gateway node 206 can execute a plugin in between an API-related request and providing an associated response to the API-related request. One advantage of the disclosed system is that the system can be expanded by adding new plugins. In some embodiments, gateway node 206 can expand the core set of functionalities by providing custom plugins. Custom plugins can be provided by the entity that operates the cluster of gateway nodes. In some instances, custom plugins are developed (e.g., built from “scratch”) by developers or any user of the disclosed system. It can be appreciated that plugins, used in accordance with the disclosed technology, facilitate in centralizing one or more common functionalities that would be otherwise distributed across the APIs, making it harder to build, scale and maintain the APIs.

Other examples of plugins can be a security plugin, a monitoring and analytics plugin, and a transformation plugin. A security functionality can be associated with the system restricting access to an API by whitelisting or blacklisting/whitelisting one or more consumers identified, for example, in one or more Access Control Lists (ACLs). In some embodiments, the security plugin requires an authentication plugin to be enabled on an API. In some use cases, a request sent by a client can be transformed or altered before being sent to an API. A transformation plugin can apply a transformations functionality to alter the request sent by a client. In many use cases, a client might wish to monitor request and response data. A monitoring and analytics plugin can allow monitoring, visualizing, and inspecting APIs and microservices traffic.

In some embodiments, a plugin is Lua code that is executed during the life-cycle of a proxied request and response. Through plugins, functionalities of a gateway node can be extended to fit any custom need or integration challenge. For example, if a consumer of the disclosed system needs to integrate their API's user authentication with a third-party enterprise security system, it can be implemented in the form of a dedicated (custom) plugin that is run on every request targeting that given API. One advantage, among others, of the disclosed system is that the distributed cluster of gateway nodes is scalable by simply adding more nodes, implying that the system can handle virtually any load while keeping latency low.

One advantage of the disclosed system is that it is platform agnostic, which implies that the system can run anywhere. In one implementation, the distributed cluster can be deployed in multiple data centers of an organization. In some implementations, the distributed cluster can be deployed as multiple nodes in a cloud environment. In some implementations, the distributed cluster can be deployed as a hybrid setup involving physical and cloud computers. In some other implementations, the distributed cluster can be deployed as containers.

FIG. 3A illustrates a block diagram of an example environment with a cluster of gateway nodes in operation. In some embodiments, a gateway node is built on top of NGINX. NGINX is a high-performance, highly-scalable, highly-available web server, reverse proxy server, and web accelerator (combining the features of an HTTP load balancer, content cache, and other features). In an example deployment, a client 302 communicates with one or more APIs 312 via load balancer 304, and a cluster of gateway nodes 306. The cluster of gateway nodes 306 can be a distributed cluster. The cluster of gateway nodes 306 includes gateway nodes 308A-308H and data store 310. The functions represented by the gateway nodes 308A-308H and/or the data store 310 can be implemented individually or in any combination thereof, partially or wholly, in hardware, software, or a combination of hardware and software.

Load balancer 304 provides functionalities for load balancing requests to multiple backend services. In some embodiments, load balancer 304 can be an external load balancer. In some embodiments, the load balancer 304 can be a DNS-based load balancer. In some embodiments, the load balancer 304 can be a Kubernetes® load balancer integrated within the cluster of gateway nodes 306.

Data store 310 stores all the data, routing information, plugin configurations, etc. Examples of a data store can be Apache Cassandra or PostgreSQL. In accordance with disclosed embodiments, multiple gateway nodes in the cluster share the same data store, e.g., as shown in FIG. 3A. Because multiple gateway nodes in the cluster share the same data store, there is no requirement to associate a specific gateway node with the data store—data from each gateway node 308A-308H is stored in data store 310 and retrieved by the other nodes (e.g., even in complex multiple data center setups). In some embodiments, the data store shares configurations and software code associated with a plugin that is installed at a gateway node. In some embodiments, the plugin configuration and code can be loaded at runtime.

FIG. 3B illustrates a schematic of a data store shared by multiple gateway nodes, according to an embodiment of the disclosed technology. For example, FIG. 3B shows data store 310 shared by gateway nodes 308A-308H arranged as part of a cluster.

One advantage of the disclosed architecture is that the cluster of gateway nodes allows the system to be scaled horizontally by adding more gateway nodes to handle a bigger load of incoming API-related requests. Each of the gateway nodes share the same data since they point to the same data store. The cluster of gateway nodes can be created in one datacenter, or in multiple datacenters distributed across different geographical locations, in both cloud or on-premise environments. In some embodiments, gateway nodes (e.g., arranged according to a flat network topology) between the datacenters communicate over a Virtual Private Network (VPN) connection. The system can automatically handle a new gateway node joining a cluster or leaving a cluster. Once a gateway node communicates with another gateway node, it will automatically discover all the other gateway nodes due to an underlying gossip protocol.

In some embodiments, each gateway includes an administration API (e.g., internal RESTful API) for administration purposes. Requests to the administration API can be sent to any node in the cluster. The administration API can be a generic HTTP API. Upon set up, each gateway node is associated with a consumer port and an admin port that manages the API-related requests coming into the consumer port. For example, port number 8001 is the default port on which the administration API listens and 8444 is the default port for HTTPS (e.g., admin_listen_ssl) traffic to the administration API.

In some instances, the administration API can be used to provision plugins. After a plugin is installed at a gateway node, it is available to be used, e.g., by the administration API or a declarative configuration.

In some embodiments, the administration API identifies a status of a cluster based on a health state of each gateway node. For example, a gateway node can be in one of the following states:

-   -   active: the node is active and part of the cluster.     -   failed: the node is not reachable by the cluster.     -   leaving: a node is in the process of leaving the cluster.     -   left: the node has left the cluster.

In some embodiments, the administration API is an HTTP API available on each gateway node that allows the user to do create, restore, update, and delete (CRUD) operations on items (e.g., plugins) stored in the data store. For example, the Admin API can provision APIs on a gateway node, provision plugin configuration, create consumers, and provision their credentials. In some embodiments, the administration API can also read, update, or delete the data. Generally, the administration API can configure a gateway node and the data associated with the gateway node in the data store.

In some applications, it is possible that the data store only stores the configuration of a plugin and not the software code of the plugin. That is, for installing a plugin at a gateway node, the software code of the plugin is stored on that gateway node. This can result in efficiencies because the user needs to update his or her deployment scripts to include the new instructions that would install the plugin at every gateway node. The disclosed technology addresses this issue by storing both the plugin and the configuration of the plugin. By leveraging the administration API, each gateway node can not only configure the plugins, but also install them. Thus, one advantage of the disclosed system is that a user does not have to install plugins at every gateway node. But rather, the administration API associated with one of the gateway nodes automates the task of installing the plugins at gateway nodes by installing the plugin in the shared data store, such that every gateway node can retrieve the plugin code and execute the code for installing the plugins. Because the plugin code is also saved in the shared data store, the code is effectively shared across the gateway nodes by leveraging the data store, and does not have to be individually installed on every gateway node.

FIG. 4A and FIG. 4B illustrate example block diagrams 400 and 450 showing ports and connections of a gateway node, according to an embodiment of the disclosed technology. Specifically, FIG. 4A shows a gateway node 1 and gateway node 2. Gateway node 1 includes a proxy module 402A, a management and operations module 404A, and a cluster agent module 406A. Gateway node 2 includes a proxy module 402B, a management and operations module 404B, and a cluster agent module 406B. Gateway node 1 receive incoming traffic at ports denoted as 408A and 410A. Ports 408A and 410A are coupled to proxy module 402B. Gateway node 1 listens for HTTP traffic at port 408A. The default port number for port 408A is 8000. API-related requests are typically received at port 408A. Port 410A is used for proxying HTTPS traffic. The default port number for port 410A is 8443. Gateway node 1 exposes its administration API (alternatively, referred to as management API) at port 412A that is coupled to management and operations module 404A. The default port number for port 412A is 8001. The administration API allows configuration and management of a gateway node, and is typically kept private and secured. Gateway node 1 allows communication within itself (i.e., intra-node communication) via port 414A that is coupled to clustering agent module 406A. The default port number for port 414A is 7373. Because the traffic (e.g., TCP traffic) here is local to a gateway node, this traffic does not need to be exposed. Cluster agent module 406B of gateway node 1 enables communication between gateway node 1 and other gateway nodes in the cluster. For example, ports 416A and 416B coupled with cluster agent module 406A at gateway node 1 and cluster agent module 406B at gateway node 2 allow intra-cluster or inter-node communication. Intra-cluster communication can involve UDP and TCP traffic. Both ports 416A and 416B have the default port number set to 7946. In some embodiments, a gateway node automatically (e.g., without human intervention) detects its ports and addresses. In some embodiments, the ports and addresses are advertised (e.g., by setting the cluster_advertise property/setting to a port number) to other gateway nodes. It will be understood that the connections and ports (denoted with the numeral “B”) of gateway node 2 are similar to those in gateway node 1, and hence is not discussed herein.

FIG. 4B shows cluster agent 1 coupled to port 456 and cluster agent 2 coupled to port 458. Cluster agent 1 and cluster agent 2 are associated with gateway node 1 and gateway node 2 respectively. Ports 456 and 458 are communicatively connected to one another via a NAT-layer 460. In accordance with disclosed embodiments, gateway nodes are communicatively connected to one another via a NAT-layer. In some embodiments, there is no separate cluster agent but the functionalities of the cluster agent are integrated into the gateway nodes. In some embodiments, gateway nodes communicate with each other using the explicit IP address of the nodes.

FIG. 5 illustrates a flow diagram showing steps of a process 500 involved in installation of a plugin at a gateway node, according to an embodiment of the disclosed technology. At step 502, the administration API of a gateway node receives a request to install a plugin. An example of a request is provided below:

-   -   For example:     -   POST/plugins/install     -   name=OPTIONAL VALUE     -   code=VALUE     -   archive=VALUE

The administration API of the gateway node determines (at step 506) if the plugin exists in the data store. If the gateway node determines that the plugin exists in the data store, then the process returns (step 510) an error. If the gateway node determines that the plugin does not exist in the data store, then the process stores the plugin. (In some embodiments, the plugin can be stored in an external data store coupled to the gateway node, a local cache of the gateway node, or a third party storage. For example, if the plugin is stored at some other location besides the data store, then different policies can be implemented for accessing the plugin.) Because the plugin is now stored in the database, it is ready to be used by any gateway node in the cluster.

When a new API request goes through a gateway node, the gateway node determines (among other things) which plugins are to be loaded. Therefore, a gateway node sends a request to the data store to retrieve the plugin(s) that has/have been configured on the API and that need(s) be executed. The gateway node communicates with the data store using the appropriate database driver (e.g., Cassandra or postgres) over a TCP communication. In some embodiments, the gateway node retrieves both the plugin code to execute and the plugin configuration to apply for the API, and then execute them at runtime on the gateway node (e.g., as explained in FIG. 6).

FIG. 6 illustrates a sequence diagram 600 showing components and associated steps involved in loading configurations and code at runtime, according to an embodiment of the disclosed technology. The components involved in the interaction are client 602, gateway node 604 (including an ingress port 606 and a gateway cache 608), data store 610, and an API 612. At step 1, a client makes a request to gateway node 604. At step 2, ingress port 606 of gateway node 604 checks with gateway cache 608 to determine if the plugin information and the information to process the request has already been cached previously in gateway cache 608. If the plugin information and the information to process the request is cached in gateway cache 608, then the gateway cache 608 provides such information to the ingress port 606. If, however, the gateway cache 608 informs the ingress port 606 that the plugin information and the information to process the request is not cached in gateway cache 608, then the ingress port 606 loads (at step 3) the plugin information and the information to process the request from data store 610. In some embodiments, ingress port 606 caches (for subsequent requests) the plugin information and the information to process the request (retrieved from data store 610) at gateway cache 608. At step 5, ingress port 606 of gateway node 604 executes the plugin and retrieves the plugin code from the cache, for each plugin configuration. However, if the plugin code is not cached at the gateway cache 608, the gateway node 604 retrieves (at step 6) the plugin code from data store 610 and caches (step 7) it at gateway cache 608. The gateway node 604 executes the plugins for the request and the response (e.g., by proxy the request to API 612 at step 7), and at step 8, the gateway node 604 returns a final response to the client.

Auto-Documentation Embodiment

When releasing an API, documentation is typically a must-have in order for developers to learn how to consume the API. Documentation for an API is an informative text document that describes what functionality the API provides, what parameters it takes as input, what is the output of the API, how does the API operate, and other such information. Usually documenting APIs can be a tedious and long task. In conventional systems, developers create an API and draft the documentation for the API. This approach to drafting a documentation for the API is human-driven. That is, the documentation is changed only when human developers make changes to the documentation. Any time the API is updated, the documentation needs to be revised. In many instances, because of pressures in meeting deadlines, developers are not able to edit the documentation at the same pace as the changes to the API. This results in the documentation not being updated which leads to frustrations because of an API having unsupported/incorrect documentation. In some unwanted scenarios, the documentation does not match the implementation of the API.

In some embodiments, the disclosed system includes a specialized plugin that automatically generates documentation for an API endpoint (e.g., input and output parameters of the API endpoint) without human intervention. By parsing the stream of requests and the responses passing through a gateway node, the plugin generates the documentation automatically. As an example, if a client sends a request to/hello, and the API associated with/hello responds back with code successfully, then the plugin realizes that/hello is an endpoint. In some embodiments, the plugin can parse the parameters involved in a request/response and identify those parameters in the generated auto-documentation. In some embodiments, the plugin can generate a response to a client's request. In some embodiments, the API itself can provide additional response headers (e.g., specifying additional about the fields, parameters, and endpoints) to generate a more comprehensive auto-documentation. For example, a client makes a request to/hello with the parameters name, age, and id. According to the disclosed auto-documentation plugin, the API provides an endpoint for the plugin to consume so that the auto-documentation plugin can obtain specific information about fields that are not obvious. For example, a “name of an entity” field that is associated with the API may be obvious. But, some other fields may not be obvious. Hypothetically, a response includes an “abcd_id” field whose meaning may not be automatically inferred by a gateway node, or which might be of interest for documentation purposes. In some embodiments, the auto-documentation generated can be specifically associated with the “abcd_id” field. The “abcd_id” field-specific documentation can be created when the user configures the auto-documentation plugin the first time. In some embodiments, the generated auto-documentation can be retrieved by a third-party source (e.g., another API). In some embodiments, the generated auto-documentation can be retrieved by a custom response header that the API endpoint returns to a gateway node.

The auto-generated documentation is in a human-readable format so that developers can understand and consume the API. When the API undergoes changes or when the request/response (e.g., parameters included in the request/response) to the API undergoes changes, the system not only auto-generates documentation but also detects changes to the request/response. Detecting the changes enables the plugin to be able to alert/notify developers when API-related attributes change (e.g., in an event when the API is updated so that a field is removed from the API's response or a new field is added in the API's response) and send the updated auto-documentation. Thus, the auto-documentation continually evolves over time.

In some embodiments, auto-documentation for an API is generated dynamically in real-time by monitoring/sniffing/parsing traffic related to requests (e.g., sent by one or more clients) and requests (e.g., received from the API). In some embodiments, the client can be a testing client. The client might have a test suite that the client intends to execute. If the client executes the test suite through a gateway node that runs the auto-documentation plugin, then the plugin can automatically generate the documentation for the test suite.

The auto-documentation output, for example, can be a Swagger (http://swagger.io/specification/) file that includes each endpoint, each parameter, each method and other API-related attributes. (A Swagger file is typically in JSON.) Thus, the auto-documentation can be in other suitable formats, e.g., RAML and API Blueprint. In some embodiments, the auto-documentation functionality is implemented as a plugin (that runs as middleware) at a gateway node.

In a microservices architecture, each microservice typically exposes a set of what are typically fine-grained endpoints, as opposed to a monolithic application where there is just one set of (typically replicated, load-balanced) endpoints. An endpoint can be considered to be a URL pattern used to communicate with an API.

In some instances, the auto-documentation can be stored or appended to an existing documentation, in-memory, on disk, in a data store or into a third-party service. In some instances, the auto-documentation can be analyzed and compared with previous versions of the same documentation to generate DIFF (i.e., difference) reports, notifications and monitoring alerts if something has changed or something unexpected has been documented.

In some embodiments, the plugin for automatically generating the documentation can artificially provoke or induce traffic (e.g., in the form of requests and responses) directed at an API so that the plugin can learn how to generate the auto-documentation for that API.

In some embodiments, when the auto-documentation plugin is generating documentation for a large number of APIs, the auto-documentation plugin can build a model using machine learning to predict what a field in the response means. By generating auto-documentation for one or more APIs, the auto-documentation plugin can learn to deal with fields and data that are not necessarily intuitive. The more APIs and endpoints are being documented, the better are the chances to automatically infer the documentation for other use-cases. The plugin could therefore build a machine learning model that it can leverage to be smarter over time, and document smarter. The machine learning model could be hosted locally within a gateway node, or can be sent to a remote (e.g., physical or cloud) server for further refinements.

FIG. 7 illustrates a sequence diagram 700 of a use-case showing components and associated steps involved in generating auto-documentation, according to an embodiment of the disclosed technology. Specifically, FIG. 7 corresponds to the use-case when the auto-documentation is generated based on pre-processing a request (e.g., sent by one or more clients) and post-processing a response (e.g., received from the API). The components involved in the interaction are a client 702, a gateway node 704, and an API 706. At step 1, a client 702 makes a request to gateway node 704. At step 2, the gateway node 704 parses the request (e.g., the headers and body of the request) and generates auto-documentation associated with the request. (The request can be considered as one part of a complete request/response transaction.) At step 3, the gateway node 704 proxies/load-balances the request to API 706, which returns a response. At step 4, the gateway node 704 parses the response (e.g., the headers and body of the response) returned by the API 706, and generates auto-documentation associated with the response. In some embodiments, the auto-documentation associated with the response is appended to the auto-documentation associated with the request. At step 5, the gateway node 704 proxies the response back to the client 702. At step 6, the resulting documentation is stored on-disk, in a data store coupled with the gateway node 704, submitted to a third-party service, or kept in-memory. In some embodiments, notifications and monitoring alerts can be submitted directly by gateway node 704, or leveraging a third-party service, to communicate changes in the generated auto-documentation or a status of the parsing process. In some embodiments, if parsing fails or the API transaction is not understood by the auto-documentation plugin, an error notification can also be sent.

FIG. 8 illustrates a sequence diagram of another use-case showing components and associated steps involved in generating auto-documentation, according to an embodiment of the disclosed technology. Specifically, FIG. 8 corresponds to the use-case when the auto-documentation is generated based on post-processing a request (e.g., sent by one or more clients) and post-processing a response (e.g., received from the API). The components involved in the interaction are a client 802, a gateway node 804, and an API 806. At step 1, a client 802 makes a request to gateway node 804. At step 2, the gateway node 804 executes all of its functionalities but does not parse the request at this point. At step 3, the gateway node 804 proxies/load-balances the request to API 806, which returns a response. At step 4, the gateway node 804 parses the request and the response, and generates auto-documentation associated with the request and the response. At step 5, the gateway node 804 proxies the response back to the client 802. At step 6, the resulting documentation is stored on-disk, in a data store coupled with the gateway node 804, submitted to a third-party service, or kept in-memory. In some embodiments, notifications and monitoring alerts can be submitted directly by gateway node 804, or leveraging a third-party service, to communicate changes in the generated auto-documentation or a status of the parsing process. In some embodiments, pre-processing a request and post-processing a response is preferred over post-processing a request and post-processing a response. Such a scenario can arise when a user wishes to document a request, even if the resulting response returns an error or fails. Typically, pre-processing a request and post-processing a response is used to partially document an endpoint. In some embodiments, the reverse is preferred. Such a scenario doesn't allow for partial documentation and is used to document the entire transaction of the request and the end response.

FIG. 9 illustrates a flow diagram 900 showing steps involved in generating auto-documentation at a gateway node, according to an embodiment of the disclosed technology. The flow diagram in FIG. 9 corresponds to the use-case when the auto-documentation is generated based on post-processing a request and post-processing a response. At step 902, a gateway node receives a client request. At step 906, the gateway node proxies the request and receives a response from the API. The response is sent back to the client. At step 910, the gateway node parses both the request and the response. At step 914, the gateway node retrieves (from local storage and remote storage of file system) the documentation for the endpoint requested. Retrieving the documentation for the endpoint is possible when the plugin has already auto-documented the same endpoint before. Upon retrieving the prior documentation, the gateway node can compare the prior documentation with the current request to identify differences. At step 918, the gateway node determines whether the endpoint exists. If the gateway node determines that the endpoint exists, then the getaway node compares (at step 922) prior documented auto-documentation (in the retrieved documentation) with the current request and response data (e.g., headers, parameters, body, and other aspects of the request and response data). If the gateway node determines that there is no difference in the prior documented auto-documentation (in the retrieved documentation) and the current request and response data, then the gateway node enters (at step 930) a “nothing to do” state in which the gateway node doesn't take any further action, and continues monitoring requests/responses to/from the API. If the gateway node determines (at step 926) that there is a difference in the prior documented auto-documentation (in the retrieved documentation) and the current request and response data, then the gateway node alerts/notifies (optionally, at step 934) a user that different auto-documentation is detected. The gateway node can notify the user via an internal alert module, sending an email to the user, or using a third-party notification service such as Pagerduty. At step 938, the gateway node determines whether the auto-documentation is to be updated. If the gateway node determines that the auto-documentation does not need to be updated, then the gateway node enters (at step 942) a “nothing to do” state in which the gateway node doesn't take any further action, and continues monitoring requests/responses to/from the API. If the gateway node determines that the auto-documentation needs to be updated, then the gateway node generates (step 946) auto-documentation for the current API transaction and stores the request and response meta-information (e.g., headers, parameters, body, etc.) in a data store or local cache. In some embodiments, if the gateway node determines at step 918 that the endpoint does not exist, then the getaway node generates auto-documentation at step 946 which includes information about the endpoint (which is newly-created). If the documentation for a specific endpoint is missing, the reason could be because the endpoint has not been requested before.

An example of a request (e.g., sent by one or more clients) is provided below:

-   -   POST/do/something HTTP/1.1     -   Host: server     -   Accept: application/json     -   Content-Length: 25     -   Content-Type: application/x-www-form-urlencoded     -   param1=value&param2=value

An example of a response (e.g., received from the API) is provided below:

-   -   HTTP/1.1 200 OK     -   Connection: keep-alive     -   Date: Wed, 7 Jun. 2017 18:14:12 GMT     -   Content-Type: application/json     -   Content-Length: 33     -   {“created”:true, “param1”:“value”}

In other embodiments, the auto-documentation functionality can be integrated with an application server or a web server, and not necessarily a gateway node. In such embodiments, the application server (or the web server) can host the API application and be an entry point for an endpoint provided by the API.

Exemplary Computer System

FIG. 10 shows a diagrammatic representation of a machine in the example form of a computer system 1000, within which a set of instructions for causing the machine to perform any one or more of the methodologies discussed herein may be executed.

In alternative embodiments, the machine operates as a standalone device or may be connected (networked) to other machines. In a networked deployment, the machine may operate in the capacity of a server or a client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment.

The machine may be a server computer, a client computer, a personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a cellular telephone or smart phone, a tablet computer, a personal computer, a web appliance, a point-of-sale device, a network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that machine.

While the machine-readable (storage) medium is shown in an exemplary embodiment to be a single medium, the term “machine-readable (storage) medium” should be taken to include a single medium or multiple media (a centralized or distributed database, and/or associated caches and servers) that store the one or more sets of instructions. The term “machine-readable medium” or “machine readable storage medium” shall also be taken to include any medium that is capable of storing, encoding or carrying a set of instructions for execution by the machine and that cause the machine to perform any one or more of the methodologies of the present invention.

In general, the routines executed to implement the embodiments of the disclosure, may be implemented as part of an operating system or a specific application, component, program, object, module or sequence of instructions referred to as “computer programs.” The computer programs typically comprise one or more instructions set at various times in various memory and storage devices in a computer, and that, when read and executed by one or more processors in a computer, cause the computer to perform operations to execute elements involving the various aspects of the disclosure.

Moreover, while embodiments have been described in the context of fully functioning computers and computer systems, those skilled in the art will appreciate that the various embodiments are capable of being distributed as a program product in a variety of forms, and that the disclosure applies equally regardless of the particular type of machine or computer-readable media used to actually effect the distribution.

Further examples of machine or computer-readable media include, but are not limited to, recordable type media such as volatile and non-volatile memory devices, floppy and other removable disks, hard disk drives, optical disks (e.g., Compact Disk Read-Only Memory (CD ROMS), Digital Versatile Discs, (DVDs), etc.), among others, and transmission type media such as digital and analog communication links.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” As used herein, the terms “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling of connection between the elements can be physical, logical, or a combination thereof. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. The word “or,” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

The above detailed description of embodiments of the disclosure is not intended to be exhaustive or to limit the teachings to the precise form disclosed above. While specific embodiments of, and examples for, the disclosure are described above for illustrative purposes, various equivalent modifications are possible within the scope of the disclosure, as those skilled in the relevant art will recognize. For example, while processes or blocks are presented in a given order, alternative embodiments may perform routines having steps, or employ systems having blocks, in a different order, and some processes or blocks may be deleted, moved, added, subdivided, combined, and/or modified to provide alternative or subcombinations. Each of these processes or blocks may be implemented in a variety of different ways. Also, while processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times. Further any specific numbers noted herein are only examples: alternative implementations may employ differing values or ranges.

The teachings of the disclosure provided herein can be applied to other systems, not necessarily the system described above. The elements and acts of the various embodiments described above can be combined to provide further embodiments.

Any patents and applications and other references noted above, including any that may be listed in accompanying filing papers, are incorporated herein by reference. Aspects of the disclosure can be modified, if necessary, to employ the systems, functions, and concepts of the various references described above to provide yet further embodiments of the disclosure.

These and other changes can be made to the disclosure in light of the above Detailed Description. While the above description describes certain embodiments of the disclosure, and describes the best mode contemplated, no matter how detailed the above appears in text, the teachings can be practiced in many ways. Details of the system may vary considerably in its implementation details, while still being encompassed by the subject matter disclosed herein. As noted above, particular terminology used when describing certain features or aspects of the disclosure should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the disclosure with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the disclosure to the specific embodiments disclosed in the specification, unless the above Detailed Description section explicitly defines such terms. Accordingly, the actual scope of the disclosure encompasses not only the disclosed embodiments, but also all equivalent ways of practicing or implementing the disclosure under the claims.

While certain aspects of the disclosure are presented below in certain claim forms, the inventors contemplate the various aspects of the disclosure in any number of claim forms. For example, while only one aspect of the disclosure is recited as a means-plus-function claim under 35 U.S.C. § 112, ¶6, other aspects may likewise be embodied as a means-plus-function claim, or in other forms, such as being embodied in a computer-readable medium. (Any claims intended to be treated under 35 U.S.C. § 112, ¶6 will begin with the words “means for.”) Accordingly, the applicant reserves the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the disclosure. 

The invention claimed is:
 1. A system for securing, managing, and extending functionalities of Application Programming Interfaces (APIs), the system comprising: a plurality of APIs; a plurality of plugins; a data store configured to store software code associated with each of the plurality of plugins and configuration associated with operation of each of the plurality of plugins; and a first and a second gateway node communicatively coupled to the plurality of APIs and the data store where data in the data store is shared by each of the first and second gateway nodes, wherein one or more of the first and the second gateway nodes are configured to: receiving, at a gateway node, a request for installing a particular plugin; upon determining, by the first gateway node, that the particular plugin is not included in the plurality of plugins; saving in the data store, by the first gateway node, software code associated with the particular plugin; retrieving, by the second gateway node, the software code associated with the particular plugin from the data store; installing, by the second gateway node, the particular plugin at the data store, using the retrieved software code associated with the particular plugin; execute a plugin in the plurality of plugins; receive an incoming request related to an API in the plurality of APIs; and proxy the incoming request to the API in the plurality of API.
 2. The system of claim 1, wherein the data store is an Apache Cassandra or a PostgreSQL.
 3. The system of claim 1, wherein the plurality of APIs include proprietary APIs, publicly available APIs, or invite-only APIs.
 4. The system of claim 1, further comprising: an administration API for configuring and installing the plurality of plugins, wherein the administration API is used for provisioning the plurality of APIs.
 5. The system of claim 4, wherein the administration API corresponds to a HTTP API.
 6. The system of claim 1, wherein requests related to an administration API is received at the first gateway node.
 7. The system of claim 1, wherein the first and second gateway nodes are based on NGINX.
 8. The system of claim 1, wherein the plurality of plugins provide functionalities of authentication, security, transformations, logging, monitoring, analytics, traffic control, and rate limiting.
 9. The system of claim 1, wherein the first gateway node includes: a first proxy port, an API port, and at least two clustering ports.
 10. The system of claim 9, wherein the first proxy port is configured to proxy HTTPS traffic, the system further including: a second proxy port.
 11. The system of claim 9, further including: an administration API port configured to expose a management API.
 12. The system of claim 9, wherein the at least two clustering ports includes a first port and a second port, the first port for intra-node communication and the second port for inter-node communication.
 13. The system of claim 9, wherein the first gateway node and the data store are included in a cluster.
 14. The system of claim 13, wherein the cluster is associated with a single datacenter.
 15. The system of claim 13, wherein the cluster is associated with multiple datacenters distributed across different geographical locations.
 16. The system of claim 13, wherein the cluster is deployed in a cloud environment or an on-premise environment.
 17. The system of claim 13, wherein the second gateway node newly joins the cluster, the system further configured to: upon the second gateway node communicating with the first gateway node, the second gateway node discovering other nodes in the cluster, based on a gossip protocol used for communications among the first and second gateway nodes. 